Concluding Remarks | AIChE

Concluding Remarks

Research Interests:

Chronic medical conditions including heart disease, hypertension, cancer, diabetes, and chronic obstructive pulmonary disease (COPD) are responsible for 7 in 10 of the deaths per year in the United States. Furthermore, 75% of the $2.9 trillion we spend on healthcare costs per year is spent of managing chronic disease conditions. Yet despite spending nearly $2,000 dollars more per person on healthcare cost than any other nation, the United States has the second lowest life expectancy among those nations. Translational research can lead to therapeutics to combat chronic diseases and as such is of critical interest to reduce chronic disease mortality. My research focuses on the identification of critical targets of the innate immune response which can provide a possible therapeutic benefit for controlling inflammation and the development of chronic conditions. I focus on the leukocyte adhesion cascade, the sequential series of binding and activation steps in which immune cells interact with the endothelium: capture and rolling, activation, firm adhesion, migration, and eventual transmigration to sites of inflammation. My current research has placed great emphasis on manipulating the steps of this cascade as it is a prerequisite for trafficking to sites of inflammation, maintaining hemostasis, and providing immuno-surveillance.

During my Ph.D. training in the department of Chemical and Biological Engineering at the University at Buffalo under Dr. Sriram Neelamegham, I studied the interaction of carbohydrate glycans, specifically sialyl-Lewis-X, with endothelial bound selectins and impact of the glycans on neutrophil trafficking during the adhesion cascade (1). Specifically, my thesis project revolved around the genetic manipulation of leukocytes by shRNA knockdowns and CRISPR/Cas9 knockouts. I sought to disrupt the all of the members of two classes of the terminal glycosyltransferases (α1,3 fucosyltransferases (2) and α2,3 sialyltransferases (3)) thought to be critical in sLex formation and thus selectin-mediated adhesion. My studies were the first genetic perturbation of the critical glycosyltransferases in both human cell lines and primary human neutrophils and lead to the eventual discovery of glycolipids as E-selectin ligands in human neutrophils (4, 5). The results highlighted stark species-specific differences between humans and mice (6) and suggests caution when examining potential disease targets based solely on mouse models.

My first post-doc with Dr. Joseph Lau in the department of Molecular and Cellular Biology at Roswell Park Cancer Institute allowed me to gain experience with animal models of glycobiology and immunology and specifically experience with in-vivo models of inflammation. Other added benefits from this time was the ability to interact with not only the clinicians at Roswell Park which gave me a perspective of what they found useful from our research which kept the overarching goal of identifying potential therapeutics in focus. My two research aims identified the effects of how defective α(1,3) fucosylation on CXCR2 chemokine receptor increased neutrophil trafficking to the inflamed lung (7) and how increasing circulatory levels of the ST6Gal-1 enzyme can inhibit mature granulocyte production in the bone marrow (8). Both of these projects are prime examples potential checkpoints which can be leveraged for clinical benefit to control the neutrophilic response to acute inflammation.

In, my current position as a postdoc with Dr. Daniel Hammer in the Department of Chemical and Biomolecular Engineering at the University of Pennsylvania Here, I have expanded my skill repertoire to include the study of the biophysics of immune cell recruitment and force generation using engineered matrices and microfluidics. For my current research project, I am investigating the unique phenomenon where HSPCs efficiently migrate against the direction of shear flow on endothelial borne CAMs, much like a salmon swims upstream. Better understanding of this phenomenon has to potential to better deliver HSPCs to the bone marrow post-transplantation.

Future Directions:

My overall research program aspires to pursue a multidisciplinary approach melding the fields of chemical engineering, bioengineering, glycobiology, molecular biology, and immunology with an overarching goal of translating basic research on immune cell trafficking into the identification of potentially exploitable therapeutic targets against chronic inflammatory diseases. My future research will focus on the genetic engineering of potential mediators of selectin-tethering and rolling, chemokine activation, and migration along the endothelial surface which have the potential for clinical benefit.

Teaching Interests:

I am strongly dedicated to the teaching and mentoring of future generations of scientists. I have experience as a teaching assistant during graduate school, as a guest lecturer as a postdoc, and have mentored numerous students in the laboratory. These range from high school and undergraduate students doing a summer internship to the direct oversight of the thesis projects of masters and Ph.D. students during my Postdoc time. I am prepared to teach all courses of both the chemical engineering and bioengineering curriculum for both undergraduates and graduate students alike. Specific courses include fluid mechanics and transport in chemical engineering and cell engineering and biotransport in bioengineering. Also, I would be able to teach electives in molecular biology, immunology, and glycobiology owing to my experience and expertise in these areas.

Relevant Works:

1. Marathe DD, Buffone A, Chandrasekaran EV, Xue J, Locke RD, Nasirikenari M, Lau JTY, Matta KL, Neelamegham S. Fluorinated per-acetylated GalNAc metabolically alters glycan structures on leukocyte PSGL-1 and reduces cell binding to selectins. Blood. 2010;115(6):1303-12. doi: 10.1182/blood-2009-07-231480. PubMed PMID: PMC2826240.

2. Buffone A, Mondal N, Gupta R, McHugh KP, Lau JTY, Neelamegham S. Silencing α1,3-Fucosyltransferases in Human Leukocytes Reveals a Role for FUT9 Enzyme during E-selectin-mediated Cell Adhesion. Journal of Biological Chemistry. 2013;288(3):1620-33. doi: 10.1074/jbc.M112.400929.

3. Mondal N, Buffone A, Stolfa G, Antonopoulos A, Lau JTY, Haslam SM, Dell A, Neelamegham S. ST3Gal-4 is the primary sialyltransferase regulating the synthesis of E-, P-, and L-selectin ligands on human myeloid leukocytes. Blood. 2014;125(4):687-96.

4. Mondal N, Stolfa G, Antonopoulos A, Zhu Y, Wang S-S, Buffone A, Atilla-Gokcumen GE, Haslam SM, Dell A, Neelamegham S. Glycosphingolipids on Human Myeloid Cells Stabilize E-Selectin–Dependent Rolling in the Multistep Leukocyte Adhesion Cascade. Arteriosclerosis, Thrombosis, and Vascular Biology. 2016;36(4):718-27. doi: 10.1161/atvbaha.115.306748.

5. Stolfa G, Mondal N, Zhu Y, Yu X, Buffone A, Neelamegham S. Using CRISPR-Cas9 to quantify the contributions of O-glycans, N-glycans and Glycosphingolipids to human leukocyte-endothelium adhesion. Scientific Reports. 2016;6:30392. doi: 10.1038/srep30392

6. Mondal N, Buffone Jr A, Neelamegham S. Distinct glycosyltransferases synthesize E-selectin ligands in human vs. mouse leukocytes. Cell Adhesion & Migration. 2013;7(3):288-92. doi: 10.4161/cam.24714.

7. Buffone A, Nasirikenari M, Manhardt CT, Lugade A, Bogner PN, Sackstein R, Thanavala Y, Neelamegham S, Lau JTY. Leukocyte-borne α(1,3)-fucose is a negative regulator of β2-integrin-dependent recruitment in lung inflammation. Journal of Leukocyte Biology. 2017;101(2):459-70. doi: 10.1189/jlb.3A0516-215RR.

8. Dougher CWL, Buffone A, Nemeth MJ, Nasirikenari M, Irons EE, Bogner PN, Lau JTY. The blood-borne sialyltransferase ST6Gal-1 is a negative systemic regulator of granulopoiesis. Journal of Leukocyte Biology. 2017. doi: 10.1189/jlb.3A1216-538RR.